In a vehicle ignition system, a power disc is used to assist the vehicle in starting power generation and supplying electric power. A conventional power disc is coupled to the crankshaft of the engine, and includes a rotor and a connecting shaft. A permanent magnet is provided on the inner periphery of the rotor. A coil stator is provided in the permanent magnet. When the motor is started, it will drive the reduction gear and the one-way clutch to turn the crankshaft and then drive the engine cylinder to run, while the crankshaft will drive the power disc to rotate, such that the rotor and the permanent magnet generate electric power by excitation to supply the electric power to the vehicle and to charge the battery.
Because the rotor is easy to wear during the process of operation, it is made of a metal material. The permanent magnet of the conventional power disc is coupled to the rotor. The entire weight of the power disc is heavier to increase the impedance of the crankshaft, which indirectly affects the engine performance and fuel consumption performance.
In order to improve the above-mentioned deficiencies, Taiwan Patent Publication No. M495039 discloses a “two-in-one structure of generator and starting motor”. A one-way clutch is connected between a crankshaft of an engine and a permanent magnet rotor of a starting motor. The permanent magnet rotor of the starting motor is provided with a generator coil rotor, so that the permanent magnet rotor of the starting motor drives the crankshaft to start the engine. The crankshaft synchronously drives the permanent magnet rotor of the generator to rotate, so that the generator coil stator produces a magnetic field to generate electric power, thereby integrating power generation and starting the motor for the starting motor to have enough torque to drive the crankshaft to save power consumption.
Taiwan Patent Publication No. M502744 discloses a “motorcycle power disc”. The outer periphery of the power disc is provided with a plurality of scales, a return-to-zero line, and a plurality of cooling holes. The rotor of the power disc is provided with a shaft, positioning scales, and a plurality of adjustment hole. The shaft of the rotor of the power disc is equipped with a strengthening ring. When the rotor of the power disc drives the power disc, the strengthening ring is used to protect the rotor of the power disc. Even if the rotor of the power disc is made of a lightweight material, it is not easy to wear.
However, although the above-mentioned patents can reduce the torque required to start the crankshaft by integrating the power generation and starting the motor or using a lightweight rotor, they cannot simultaneously improve the charging efficiency of the battery. Accordingly, the inventor of the present invention has devoted himself based on his many years of practical experiences to solve these problems.